diff --git a/Chapter3-3-1/src/main/java/com/didispace/service/UserService.java b/Chapter3-3-1/src/main/java/com/didispace/service/UserService.java
index 6905546..de6745d 100644
--- a/Chapter3-3-1/src/main/java/com/didispace/service/UserService.java
+++ b/Chapter3-3-1/src/main/java/com/didispace/service/UserService.java
@@ -1,6 +1,8 @@
 package com.didispace.service;
 
 import com.didispace.domain.User;
+import org.springframework.transaction.annotation.Propagation;
+import org.springframework.transaction.annotation.Isolation;
 import org.springframework.transaction.annotation.Transactional;
 
 
@@ -9,7 +11,7 @@ import org.springframework.transaction.annotation.Transactional;
  */
 public interface UserService {
 
-    @Transactional
+    @Transactional(isolation = Isolation.DEFAULT, propagation = Propagation.REQUIRED)
     User login(String name, String password);
 
 }